The use of labels for rubber-based substrates, such as vehicular tires and the like, is well known. The labels are typically comprised of a facestock and an adhesive layer. A release liner, which is removably adhered to the adhesive layer, is usually included with these labels. The release liner is stripped from the label when it is desired to affix the label to the rubber-based substrate. A problem with the use of these label constructions is that the adhesive layer and/or the rubber-based substrate often contain migratory components (e.g., oils, plasticizers, carbon black, and the like) that migrate to the facestock and cause distortion and/or color deterioration of the facestock. The present invention, which employs a radiation cured cross linked acrylated epoxy barrier layer between the facestock and the adhesive layer, overcomes this problem by shielding the facestock from these migratory components.
Another application for laminates is for signs on vehicles. Typically additives are placed in the facestock to help the facestock maintain its performance properties over time. The sign may be used on the side of vehicles for the purposes of advertisement, decoration, and/or information. The desirable functional features of such laminates, include the ability to conform well over rivets and corrugation (to look as though the graphics containing laminate signs were painted); offer excellent reception to various type of printing inks; tolerate a wide variation in outdoor weather conditions such as rain, solar irradiation, winter as well as summer temperatures; remove cleanly when desired from the side of these vehicles without leaving adhesive residue or film breaking due to becoming brittle and offer sufficient adhesion to various metal and painted substrates over a wide range of temperatures spanning from summer to winter months.
Additives are often added to the facestocks, such as vinyl facestocks to maintain the facestock's pliability and removability. For signs, this is particularly important since the sign needs to be conformable to the surface of vehicles. However, these additives tend to migrate to the adhesive. This migration causes the adhesive to have reduced removability. This invention concerns pressure sensitive adhesive laminates that are used to make signs. The present invention, which employs a radiation cured cross linked acrylated epoxy barrier layer between the facestock and the adhesive layer, overcomes this problem by shielding the adhesive from these migratory components.
U.S. Pat. No. 5,612,107 discloses a composite construction that comprises (A) a layer of plasticized polymer film having a face side and a back side; (B) a release-coated liner having one surface in contact with the back side of the layer of plasticized polymer film; and either (C) a plasticizer-resistant polymer backcoating on the other surface of the release-coated liner (B) which is essentially impervious to the plasticizer in (A); or (D) a removable plasticizer-resistant polymer film in contact with the face side of the layer of plasticized polymer film (A). These composite constructions are capable of being wound upon themselves in roll form and may be readily unwound for use. When unwound, the presence of mottling on the surface of the vinyl film is observed to be minimized or eliminated.
U.S. Pat. No. 6,235,363 discloses a composite construction that comprises (A) a first substrate; (B) an adhesive layer; and (C) a barrier layer positioned between the first substrate and the adhesive layer. The barrier layer comprises a radiation cured cross linked cycloaliphatic epoxide derived from at least one cycloaliphatic epoxy compound, at least one polyol and at least one photoinitiator. The barrier layer is substantially impervious to migratory components in the first substrate.